266,202 research outputs found
Feline hypersomatotropism and acromegaly tumorigenesis: a potential role for the AIP gene
Acromegaly in humans is usually sporadic, however up to 20% of familial isolated pituitary adenomas are caused by germline sequence variants of the aryl-hydrocarbon-receptor interacting protein (AIP) gene. Feline acromegaly has similarities to human acromegalic families with AIP mutations. The aim of this study was to sequence the feline AIP gene, identify sequence variants and compare the AIP gene sequence between feline acromegalic and control cats, and in acromegalic siblings. The feline AIP gene was amplified through PCR using whole blood genomic DNA from 10 acromegalic and 10 control cats, and 3 sibling pairs affected by acromegaly. PCR products were sequenced and compared with the published predicted feline AIP gene. A single nonsynonymous SNP was identified in exon 1 (AIP:c.9T > G) of two acromegalic cats and none of the control cats, as well as both members of one sibling pair. The region of this SNP is considered essential for the interaction of the AIP protein with its receptor. This sequence variant has not previously been reported in humans. Two additional synonymous sequence variants were identified (AIP:c.481C > T and AIP:c.826C > T). This is the first molecular study to investigate a potential genetic cause of feline acromegaly and identified a nonsynonymous AIP single nucleotide polymorphism in 20% of the acromegalic cat population evaluated, as well as in one of the sibling pairs evaluated
Hadron Spectroscopy - A 2005 Snapshot
Some aspects of hadron spectroscopy are reviewed as of summer 2005.Comment: 15 pages, 8 figures, invited talk presented at Physics in Collision
2005, Prague, Czech Republic, July 7-9, 2005. Proceedings to be published by
AIP. Uses AIP style files. Typo correcte
The role of magnetic fields on the transport and efficiency of aluminum tris(8-hydroxyquinoline) based organic light emitting diodes
Copyright 2007 AIP Publishing LLC. This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Journal of Applied Physics [102, 073710 (2007)] and may be found at
Pauli-Villars Regularization in nonperturbative Hamiltonian approach on the Light Front
The advantage of Pauli-Villars regularization in quantum field theory
quantized on the light front is explained. Simple examples of scalar
field theory and Yukawa-type model are used. We give also an
example of nonperturbative calculation in the theory with Pauli-Villars fields,
using for that a model of anharmonic oscillator modified by inclusion of ghost
variables playing the role similar to Pauli-Villars fields.Comment: LaTeX, 10 pages, 2 figures. Article will be published in AIP
Conference Proceedings, the final publication will be available at
http://scitation.aip.org/content/aip/proceeding/aipc
Dynamic flow distortion investigation in an S-duct using DDES and SPIV data
The dynamic flow distortion generated within convoluted aero-engine intakes can affect the performance and operability of the engine. There is a need for a better understanding of the main flow mechanisms which promote flow distortion at the exit of S-shaped intakes. This paper presents a detailed analysis of the main coherent structures in an S-duct flow field based on a Delayed Detached Eddy Simulation (DDES). The DDES capability to capture the characteristics of the highly unsteady flow field is demonstrated against high resolution, synchronous Stereoscopic Particle Image Velocimetry (SPIV) measurements at the Aerodynamic Interface Plane (AIP). The flow field mechanisms responsible for the main AIP perturbations are identified. Clockwise and counter-clockwise stream-wise vortices are alternately generated around the separation region at a frequency of St=0.53, which promotes the swirl switching at the AIP. Spanwise vortices are also shed from the separation region at a frequency of St=1.06, and convect downstream along the separated centreline shear layer. This results in a vertical modulation of the main loss region and a fluctuation of the velocity gradient between the high and low velocity flow at the AIP
AIP and MEN1 mutations and AIP immunohistochemistry in pituitary adenomas in a tertiary referral center.
Background: Pituitary adenomas have a high disease burden due to tumor growth/
invasion and disordered hormonal secretion. Germline mutations in genes such as MEN1
and AIP are associated with early onset of aggressive pituitary adenomas that can be
resistant to medical therapy.
Aims: We performed a retrospective screening study using published risk criteria to
assess the frequency of AIP and MEN1 mutations in pituitary adenoma patients in a
tertiary referral center.
Methods: Pituitary adenoma patients with pediatric/adolescent onset, macroadenomas
occurring ≤30 years of age, familial isolated pituitary adenoma (FIPA) kindreds and
acromegaly or prolactinoma cases that were uncontrolled by medical therapy were
studied genetically. We also assessed whether immunohistochemical staining for
AIP (AIP-IHC) in somatotropinomas was associated with somatostatin analogs (SSA)
response.
Results: Fifty-five patients met the study criteria and underwent genetic screening for
AIP/MEN1 mutations. No mutations were identified and large deletions/duplications were
ruled out using MLPA. In a cohort of sporadic somatotropinomas, low AIP-IHC tumors
were significantly larger (P = 0.002) and were more frequently sparsely granulated
(P = 0.046) than high AIP-IHC tumors. No significant relationship between AIP-IHC and
SSA responses was seen.
Conclusions: Germline mutations in AIP/MEN1 in pituitary adenoma patients are rare and
the use of general risk criteria did not identify cases in a large tertiary-referral setting.
In acromegaly, low AIP-IHC was related to larger tumor size and more frequent sparsely
granulated subtype but no relationship with SSA responsiveness was seen. The genetics
of pituitary adenomas remains largely unexplained and AIP screening criteria could be
significantly refined to focus on large, aggressive tumors in young patients
On the nature of black hole entropy
I argue that black hole entropy counts only those states of a black hole that
can influence the outside, and attempt (with only partial success) to defend
this claim against various objections, all but one coming from string theory.
Implications for the nature of the Bekenstein bound are discussed, and in
particular the case for a holographic principle is challenged. Finally, a
generalization of black hole thermodynamics to "partial event horizons" in
general spacetimes without black holes is proposed.Comment: 13 pages, 2 figures; references added, almost same as version
published in General Relativity And Relativistic Astrophysics: Eighth
Canadian Conference, AIP Conference Proceedings 493, eds. C.P. Burgess and
R.C. Myers (AIP, 1999
Dynamics of a coefficient of friction during non-stationary sliding of a parabolic indenter on visco-elastic foundation
This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in AIP Conference Proceedings 1783, 020041 (2016) and may be found at https://doi.org/10.1063/1.4966334.We have studied the coefficient of friction between a rigid parabolic indenter and a visco-elastic Kelvin foundation under step-wise change of sliding velocity. We have obtained analytical estimations for normal and tangential forces in a contact and their limiting values during transition process that occurs after a jump of sliding velocity. The results of numerical simulation are in good agreement with analytical estimates
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